As the joint structure of the diverging branch pipe in the fuel rail for the internal combustion engine, there is a structure in which a joint fitting (nipple) is mutually joined (brazed, etc.) to a through hole communicated with a circulating path arranged in a circumferential wall portion of a rail main body in a fitting insertion state, and the diverging branch pipe is fastened and connected to this joint fitting by a nut (see JP-A-2003-278623). In the joint of the diverging branch pipe in the fuel rail for the direct injection gasoline engine of such a structure, nickel plating is performed on at least the inner circumferential faces of the fuel rail and the diverging branch pipe and the surface of an iron foundation, or a copper plating film for brazing and a copper solder material is covered to prevent corrosion due to oxidation of the fuel. However, in the joint structure of the above structure, the fuel (gasoline) has an oxidizing action by direct contact with the surface of the iron foundation, or the copper plating film and the copper solder material in the circulating path, and is oxidized. Sour gasoline raised in corrosive property by the oxidation corrodes the iron foundation or the aluminum surface of a constructional part. Therefore, electroless nickel plating is performed in an entire product, and a nickel plating film is arranged on the inner circumferential faces of the rail and the branch joint. Further, in view of the prevention of atmospheric pollution, a method for performing chemical tinning after copper brazing instead of the above electroless nickel plating is also known (JP-A-11-117826). Further, a structure for forming Ni or a Ni base alloy plating film on the inner and outer faces of the fuel rail is known. Further, a structure for setting the diverging branch pipe to a double pipe is also known. In this structure, a SUS pipe or an alloy plating pipe of Ni or a Ni base on the inner face is used on the inner pipe side, and this inner face is set to the alloy plating pipe of the Ni base. The plating layer of one kind among Ni, Co and alloys with these elements as bases is formed as a first plating layer. A single metal or an alloy layer having a melting point lower than that of the above first plating layer forming metal or an alloy with these metals as bases is formed as a second plating layer on this first plating layer. Electric sewing tubulization is performed by using a band steel plate forming these two plating layers therein. Next, it is known that a welding pipe (JP-A-5-9786 and JP-A-5-156494) having no exposed portion of the steel foundation by performing heating processing is used.